/*
 * wpa_supplicant/hostapd / OS specific functions for UNIX/POSIX systems
 * Copyright (c) 2005-2006, Jouni Malinen <j@w1.fi>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Alternatively, this software may be distributed under the terms of BSD
 * license.
 *
 * See README and COPYING for more details.
 */

#include "includes.h"

#include "os.h"

void os_sleep(os_time_t sec, os_time_t usec)
{
        if (sec)
                sleep(sec);
        if (usec)
                usleep(usec);
}


int os_get_time(struct os_time *t)
{
        int res;
        struct timeval tv;
        res = gettimeofday(&tv, NULL);
        t->sec = tv.tv_sec;
        t->usec = tv.tv_usec;
        return res;
}


int os_mktime(int year, int month, int day, int hour, int min, int sec,
              os_time_t *t)
{
        struct tm tm, *tm1;
        time_t t_local, t1, t2;
        os_time_t tz_offset;

        if (year < 1970 || month < 1 || month > 12 || day < 1 || day > 31 ||
            hour < 0 || hour > 23 || min < 0 || min > 59 || sec < 0 ||
            sec > 60)
                return -1;

        memset(&tm, 0, sizeof(tm));
        tm.tm_year = year - 1900;
        tm.tm_mon = month - 1;
        tm.tm_mday = day;
        tm.tm_hour = hour;
        tm.tm_min = min;
        tm.tm_sec = sec;

        t_local = mktime(&tm);

        /* figure out offset to UTC */
        tm1 = localtime(&t_local);
        if (tm1) {
                t1 = mktime(tm1);
                tm1 = gmtime(&t_local);
                if (tm1) {
                        t2 = mktime(tm1);
                        tz_offset = t2 - t1;
                } else
                        tz_offset = 0;
        } else
                tz_offset = 0;

        *t = (os_time_t) t_local - tz_offset;
        return 0;
}


#ifdef __APPLE__
#include <fcntl.h>
static int os_daemon(int nochdir, int noclose)
{
        int devnull;

        if (chdir("/") < 0)
                return -1;

        devnull = open("/dev/null", O_RDWR);
        if (devnull < 0)
                return -1;

        if (dup2(devnull, STDIN_FILENO) < 0) {
                close(devnull);
                return -1;
        }

        if (dup2(devnull, STDOUT_FILENO) < 0) {
                close(devnull);
                return -1;
        }

        if (dup2(devnull, STDERR_FILENO) < 0) {
                close(devnull);
                return -1;
        }

        return 0;
}
#else /* __APPLE__ */
#define os_daemon daemon
#endif /* __APPLE__ */


int os_daemonize(const char *pid_file)
{
#ifdef __uClinux__
        return -1;
#else /* __uClinux__ */
        if (os_daemon(0, 0)) {
                perror("daemon");
                return -1;
        }

        if (pid_file) {
                FILE *f = fopen(pid_file, "w");
                if (f) {
                        fprintf(f, "%u\n", getpid());
                        fclose(f);
                }
        }

        return -0;
#endif /* __uClinux__ */
}


void os_daemonize_terminate(const char *pid_file)
{
        if (pid_file)
                unlink(pid_file);
}


int os_get_random(unsigned char *buf, size_t len)
{
        FILE *f;
        size_t rc;

        f = fopen("/dev/urandom", "rb");
        if (f == NULL) {
                printf("Could not open /dev/urandom.\n");
                return -1;
        }

        rc = fread(buf, 1, len, f);
        fclose(f);

        return rc != len ? -1 : 0;
}


unsigned long os_random(void)
{
        return random();
}


char * os_rel2abs_path(const char *rel_path)
{
        char *buf = NULL, *cwd, *ret;
        size_t len = 128, cwd_len, rel_len, ret_len;
        int last_errno;

        if (rel_path[0] == '/')
                return strdup(rel_path);

        for (;;) {
                buf = malloc(len);
                if (buf == NULL)
                        return NULL;
                cwd = getcwd(buf, len);
                if (cwd == NULL) {
                        last_errno = errno;
                        free(buf);
                        if (last_errno != ERANGE)
                                return NULL;
                        len *= 2;
                        if (len > 2000)
                                return NULL;
                } else {
                        buf[len - 1] = '\0';
                        break;
                }
        }

        cwd_len = strlen(cwd);
        rel_len = strlen(rel_path);
        ret_len = cwd_len + 1 + rel_len + 1;
        ret = malloc(ret_len);
        if (ret) {
                memcpy(ret, cwd, cwd_len);
                ret[cwd_len] = '/';
                memcpy(ret + cwd_len + 1, rel_path, rel_len);
                ret[ret_len - 1] = '\0';
        }
        free(buf);
        return ret;
}


int os_program_init(void)
{
        return 0;
}


void os_program_deinit(void)
{
}


int os_setenv(const char *name, const char *value, int overwrite)
{
        return setenv(name, value, overwrite);
}


int os_unsetenv(const char *name)
{
#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__APPLE__) || \
    defined(__OpenBSD__)
        unsetenv(name);
        return 0;
#else
        return unsetenv(name);
#endif
}


char * os_readfile(const char *name, size_t *len)
{
        FILE *f;
        char *buf;

        f = fopen(name, "rb");
        if (f == NULL)
                return NULL;

        fseek(f, 0, SEEK_END);
        *len = ftell(f);
        fseek(f, 0, SEEK_SET);

        buf = malloc(*len);
        if (buf == NULL) {
                fclose(f);
                return NULL;
        }

        if (fread(buf, 1, *len, f) != *len) {
                fclose(f);
                free(buf);
                return NULL;
        }

        fclose(f);

        return buf;
}


void * os_zalloc(size_t size)
{
        return calloc(1, size);
}


size_t os_strlcpy(char *dest, const char *src, size_t siz)
{
        const char *s = src;
        size_t left = siz;

        if (left) {
                /* Copy string up to the maximum size of the dest buffer */
                while (--left != 0) {
                        if ((*dest++ = *s++) == '\0')
                                break;
                }
        }

        if (left == 0) {
                /* Not enough room for the string; force NUL-termination */
                if (siz != 0)
                        *dest = '\0';
                while (*s++)
                        ; /* determine total src string length */
        }

        return s - src - 1;
}
